1. Field of the Invention
The present invention relates generally to systems for maintaining a dry atmosphere. More specifically, the present invention relates to a solar powered air drying system which maintains a dry atmosphere inside of a sealed volume.
2. Description of the Prior Art
Radio Frequency (RF) targets located at remote sites on military test facilities have a history of degradation caused by moisture condensation inside the target's waveguide run and antenna.
Currently, fuel powered dry air systems are used to pressurize the waveguide run and antenna of radio frequency targets to prevent moisture from corroding the waveguide run and antennas. However, when a fuel powered dry air system at a remote site runs out of fuel, a considerable time period may elapse before personnel return to the site to refuel the system. This allows condensation to occur resulting in corrosion damage to the waveguide run and antenna.
Moisture accumulates within the sealed volume/housing of the waveguide run and antenna of a target because of daily temperature cycles. During the day, air volume temperature increases within the housing pushing a small amount of air out of the housing through leaks and/or openings in the housing. At night, air volume temperature decreases drawing moist air into the housing. As this cycle is repeated over several days, moisture levels within the housing will increase resulting in a sufficient accumulation of moisture within the housing to generate condensation at night when temperatures are generally lower than during the day. This condensation causes corrosion of the targets waveguide run and antenna that will significantly degrade the performance of the target.
Alternative approaches to an air drying system include wrapping the sealed volume/housing inside a sealed bag, adding desiccant to the sealed volume and allowing the sealed volume to breathe through a desiccated breather. Wrapping a waveguide run inside a sealed bag is impractical after the waveguide run is installed in the Radio Frequency target. Placing desiccant inside the sealed volume of the waveguide run and antenna would be effective, however desiccant would interfere with Radio Frequency energy. A branch for housing the desiccant could be added to the waveguide run. Moisture control would be minimal because only a small amount of air would be exchanged between the main waveguide run as the temperature changed. Allowing the sealed volume to breathe is effective, however, it requires that the desiccant be changed periodically.
Accordingly, there is a need for an air drying system for maintaining a dry atmosphere inside of a sealed volume which can be placed at a remote location to prevent corrosion of a target's waveguide run and antenna located within the sealed volume.